Angularly adjustable boomsuspended bucket



Sept. 8, 1953 J. M. JOHNSON 2,651,424

3 Sheets-Sheet l INVENTOR 2% wag-[91W aim ATTORNEYS Sept. 8, 1953 J. M. JOHNSON 2,651,424 ANGULARLY ADJUSTABLE BOOM-SUSPENDED BUCKET Filed Nov. 10, 1949 s Sheets$heet 2 v w \1 v a v INVENTOR 'L/a )wv M (hams-om fimem v 0mm ATTORNEYS Sept. 8, 1953 J. M. JOHNSON 2,651,424 ANGULARLY ADJUSTABLE BOOMSUSPENDED' BUCKET Filed Nov 10, 1949 25 Sheefs-Sheet I5 INVENTOR 44 day/v /V. a/o/m/s/v Patented Sept. 8, 1953 ANGULARLY ADJUSTABLE BOOM- SUSPENDED BUCKET John M. Johnson, Floodwood, Minn. Application November 10, 1949, Serial No. 126,611

1 This invention relates to portable hoist devices, and more particularly to a tractor mounted crane device of the fluid pressure operated type.

A main object of the invention is to provide a novel and improved crane which maybe mounted on a bulldozer or a tractor, said crane being simple in construction; easy to install, and having a high loading capacity. 7 n

A further object of the invention is to provide an improved crane for use on a bulldozer or tractor, said crane being inexpensive to fabricate, being easy to control, and being very flexible in operation.

' Further objects'and advantages of the invention wil1 become apparent from the following description and claims, and from the accompanying drawings,- wherein: I Figure 1 is a side elevational view of a tractor mounted crane constructed in accordance with the present invention;

Figure 2 is a top plan view of the crane of Figure 1; I

Figure 3 is a front-end elevational view of the crane shown in Figures 1 and 2; Figure 4 is an enlarged cross-sectional detail view taken on line 4--4 of Figure'2 Figure 5 is a schematic diagram of the conduit connections employed in the-crane of Figures 1 to 4. 1 e g Referring to the drawings, I I designates a'conventional tractor, such as abulldozer tractor. Designed at I2, I2 are verticalarms fixed to the sides of the frame of the-tractor, and pivoted to the. top endsof the respective arms I2, I2 at I3, I3 are the vertically swingable, forwardlyextendingarms I4, I4. Rigidlysecured to the rear portions of the sides of the tractorframe are the upstanding boom supports I6, I6. .Designated generally at I5 isa boom comprisinglongitudinal .side arm portions-I1, l! which are respectively pivoted at I8, I8. to the topends of the boom supports I6, Hi. The side arm, portions I1, I! are connected at theintermediate portion of the boom by a transverse beam,I9. Secured to the respective end portions of beam I9 are respective pairs of parallel, depending arms 20, 2 I. Pivoted to. the end of each. of the arms I4 is a sleeve member 22. Each sleeve member 22 has adjustablythreaded thereinto the threaded shank 23 of an eye bolt 25.. Each eyebolt' 25 is pivotally secured between the ends of a pair of the depending arms 20, 2I by a transverse pivot pin 24 seicured to said ends, as shown in Figure 3.

. Designated at 26, 26 are respective fluid pressure cylinders pivotedto the frame of tractor II at.2'|, 21. Each cylinder 26 contains a piston having a piston rod 28 extending slidably and .sealingly through the upper end wall of the cylinder, each piston rod 28 being pivotally connected'at 29 to a rear upper portion of a respective arm I4, as shown in Figure 1. From Fig- 2 Claims. (Cl. 214147) 2 ure 1 it will be seen that when the piston rods 28 are extended forwardly from the cylinders 26. the arms I4 will be rotated counterclockwise from the full line positions thereof to the dotted line position shown in Figure 1, whereby the boom I5 will be lowered from its full line positionto its dotted line position.

The side arms l1, l1 converge forwardly, as shown at 30, 30 and are connected at their forward ends by a transverse crossbar 3I. The side arm portions 30, 30 are formed adjacent crossbar 3| with opposing apertured bearing lugs 32, 32. Rotatably mounted in said bearing lugs is a transverse shaft 33, and secured on said shaft is a square plate 34. Designated at 35 is a vertical shaft extending rotatably through the center of the plate 34. Welded to the top end portion of shaft 35 is a square bearing plate member 36 formed with a diagonally extending arm 31. Pivotally connected by a universal joint 5I to the end of arm 3'! is the end of a piston rod 38. Piston rod 38 extends from .a. fluid pressure cylinder 39 which is pivotally secured'at 46 to an inwardly extending bracket 4I carried by one of the side arm portions 30. Piston rod 38 is secured to a piston contained in cylinder 39 and extends slidably and sealingly through the forward end Wall of the cylinder.

Rigidly secured to the lower end portion of shaft 35 are spaced parallel vertical plate members 42, 42. A transverse pin member 43 connects the lower intermediate portions of the plate members 42, 42 and pivotally connects the upper end of a fluid pressure cylinder 44 between said plate members. each plate member 42 are downwardly and outwardly inclined supportbars 45, 45'. The bars 45' are pivotally secured to the plate members 42 at 42'. Designated at 46, 41 are the bucket jaws, each jaw being pivotally connected at 48, 48 to the lower ends of a pair of support bars for rotation around a transverse axis. The top ends of the bucket jaws are loosely pivotally connected together by a transverse shaft 49, as shown in Figure 3, said shaft extending loosely. through said top ends. Cylinder 44 contains a piston having a piston rod 50 extending slidably and sealingly through the lower end wall of the cylinder and being pivotally connected to the intermediate portion of the transverse shaft 49.

When fluid underpressure is admitted to the cylinder 39, the shaft 35 will be rotated, causing the bucket jaws 46, 41 to be rotated around the axis of said shaft. Due to the pivotal connection of shaft 33 in the bearing lugs 32, ,32, the weight of the jaws maintains said axis verticalat all times. When fluid under pressure is'admitted to the top portion of cylinder 44, the piston rod 56 is moved, downwardly, causing the top portions of the jaws to be depressed, therebyopening the jaws. The loose connection of shaft 49 to said v top portions and the pivotal connections 42 of Secured to the side margins of support bars 45' allow said top portions to be moved downwardly from their positions of Figure 1.

It will be apparent that the elevation of boom is controlled by cylinders 26, 26, the direction of orientation of the jaws controlled by cylinder 39, and that the opening and closing of said jaws is controlled by the cylinder 44.

Referring now to Figure 5, it will'be seen that a fluid supply reservoir 52 is provided, said reservoir being mounted on the front end of the tractor frame, as shown in Figures 1 and 2. Also provided on the frame are the respective fluid pumps 53 and 54, driven in any suitable manner from the tractor engine. Extending from tank 52 to pump 54 is a fluid supply conduit 55. Extending from the outlet of pump 54 through a by-pass relief valve 56 is a conduit 57. Connected to conduit 57 are respective conduits 58, 58. Conduits 58, 58' communicate with conduits 59, 59' through respective reversing valves 60, 69. Conduits 59, 59' are respectively connected to the forward ends of the cylinders 39, 44. Designated at 6!, 6| are respective conduits extending from the rear ends of the cylinders 39, 44 through the respective reversing valves 69, 66' and return lines 64, 64' to a return conduit 62 leading to reservoir 52. A by-pass conduit 63 connects relief valve 56 to the return line 64.

Valve 60 may be set to admit fluid into the forward end of cylinder 39 and to allow fluid to discharge from the rear end thereof. This rotates arm 31 clockwisaas viewed in Figure 2, causing the bucket jaws to swing clockwise. By reversing the position of valve 69, fluid may be admitted into the rear end. of cylinder 39 and allowed to discharge from the front end thereof. This retracts the plunger of cylinder 39 and swings the bucket jaws counterclockwise, as viewed in Figure 2.

Similarly, valve 66' may be set to admit fluid into the top end of cylinder 44 and to allow fluid to discharge from the lower end thereof. This depresses shaft 49, opening the jaws. By reversing the position of valve 60', fluid may be admitted into the lower end of cylinder 44 and allowed to discharge from the upper end of said cylinder. This retracts the plunger of cylinder 44, closing the jaws.

Relief valve 56 operates. in. a conventional manner. to by-pass fluid from supply conduit 51 through by-pass conduit 63 to return conduit 64 when the pressure in conduit 51 builds up to an excessive value, asv where both valves and 60 are set to closed positions.

It will be further seen from Figure 5- that a supply conduit 64 extends from tank 52 to pump 53 and that a conduit 65 extends from the outlet of pump 53 through a reversing valve 66- to conduits 61, 61 connected to the forward ends of cylinders 26, 26. Return conduits 66, 68 from the rear ends of cylinders 26, 26 are connected through reversing valve 66 to a return line 69 leadin to the tank 52. Valve 66 may be set to admit fluid into the forward ends of cylinders 26, 26, allowing fluid to discharge from the rear ends of said cylinders. This retracts the piston rods 28, causing the arms I4 to be rotated clockwise, as viewed in Figure 1, thereby elevating the boom I 5. Similarly, valve 66 may be set to admit fluid into the rear ends of cylinders 26, 26, allowing fluid to discharge from the forward ends of the cylinders. This extends piston rods 28, causing arms M to rotate counterclockwise, as viewed in Figure 1, thereby lowering the boom.

By manipulating the control valves 66, 60 and 60' in the manner above described, the bucket jaws maybe raised and lowered, may be oriented in a desired direction, and may be opened and closed, as required. By virtue of the pivotal connection of the bucket supporting shaft 33 in the bearing lugs 32, 32, the bucket jaws are maintained in vertical depending positions at all times, whereby the bucket jaws are maintained in balanced relation and whereby undue wear due to unbalanced loading on the bucket pivot elements is avoided.

While a specific embodiment of a fluid pressure operated portable crane has been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore, it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.

What is claimed is:

1. In a crane having an angularly adjustable boom, a shaft journaled on the boom for rotary movement about an axis transverse to the longitudinal axis of the boom, a plate fixed to the shaft with the face of the plate parallel to the axis of the shaft, a member rotatably superimposed on the plate, a pin carried by the member and rotatably extending through the plate, a supporting structure suspended on the pin and secured to the pin for rotation therewith, said pin and supporting structure being free to hang vertically in all angular positions of the boom by virtue of the rotation of said shaft, a grappling member secured to the supporting structure, an arm extending from the member, and hydraulic actuating means carried by the boom and operatively connected to the arm for rotating the pin and grappling member.

2. In a crane having an angularly adjustable boom, a shaft iournaled on the boom for rotary movement about an axis transverse to the longitudinal axis of the boom, a plate fixed to the shaft with'the face of the plate parallel to the axis of the shaft, a member rotatably superimposed on the plate, a pin carried by the member and rotatably extending through the plate, a supporting structure suspended on the pin and secured to the pin for rotation therewith, said pin and supporting structure being free to hang vertically in all angular positions of the boom-by virtue of the rotation of said shaft, 2. grappling member secured to the supporting structure, an arm extending from the member, a hydraulic cylinder pivotally carried by the boom, 2. piston rod operatively extending from the cylinder, and universal means-connecting said piston rod to the arm.

JOHN M. JOHNSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 994,506 Falcone June 6, 1911 1,518,560 Carroll Dec. 9, 1924 1,773,478 Dovel Aug. 19, 1930 2,387,764 Maxwell Oct. 30, 1945 2,426,544 Wooldridge Aug. 26, 1947 2,474,374 Shattuck June 28, 1949 2,477,401 Billings July 26, 1949 2,488,767 Drott et al Nov. 22, 1949 2,496,696 Burner Feb. 7', 1950 2,500,887 Trlssler Mar. 14, 1950 

